Even the best-constructed buildings may suffer structural problems as time goes on. Such problems are often the result of changes in the building’s sub-base – that is, the soil and rocks beneath your foundation. Even seemingly stable sub-bases may shift and sink with time, often causing cracks and other forms of foundation damage to your Houston, TX home.
Fortunately, you can mediate the ill effects of a shifting sub-base through the foundation repair technique known as pier underpinning. If you would like to improve your understanding of this incredibly effective procedure, read on. This article will provide a handy overview of pier underpinning.
What is Pier Underpinning?
Simply put, a foundation relies on contact with a stable base in order to support the weight of your home. If a shifting sub-base has left portions of your foundation without direct support, those areas will be at a much greater risk of suffering damage. Underpinning refers to the technique of shoring up an under supported foundation with additional supports.
The simplest method of underpinning involves adding a brand new concrete slab to the underside of the foundation. This acts to fill in any gaps that may be present, while also ensuring that the foundation will be relatively protected against any future shifts. Of course, the massive amount of concrete this requires can sometimes be prohibitive.
An alternative method involves adding such concrete only to certain key locations. An experienced foundation contractor can identify which weak spots are most in need of reinforcement. They then add concrete pillars in these places. This method is most commonly referred to as box underpinning.
Be aware that both methods of concrete underpinning may be susceptible to the same problems that affected your original foundation. In other words, if the sub-base continues to shift or sink, the foundation may crack. Over time, this could potentially lead to the underpinning not being able to provide the necessary degree of strength and stability.
Pier underpinning departs significantly from the approaches of concrete based underpinning. Here the material of choice is metal, which presents two key advantages. First of all, metal pier systems are not susceptible to the cracking and structural instability that can plague concrete underpinning, should the subbase continue to shift.
The second benefit of metal pier systems is that they tend to be much easier to install. Concrete underpinning requires that a significant portion of soil beneath your home be excavated and disposed of somehow. Metal pier systems have a much smaller footprint and can be installed much less invasive.
Metal pier systems can be broken down into two main categories: push piers and helical piers. Push piers utilize galvanized steel tubes that are held in place by means of metal brackets. When installing push piers, the brackets are first put in place, then the piers are pushed down through them into the ground using a hydraulic press.
The length of a particular pier depends on how deep the stable bedrock is. A trained structural engineer will find the bedrock and assess the number and location of piers needed.
Unlike push piers, which are made of smooth metal, helical piers have round plates evenly spaced along their length. These plates help to anchor the piers in the ground, making them less susceptible to heaving soil. The plates add enough stability to underpin a foundation in the event the bedrock layer is too deep for push piers to contact.
If you suspect that your home’s foundation has suffered damage, know the different methods by which it might be repaired. Make sure you contact a foundation repair company with the right combination of knowledge and experience. For more information about shoring up your foundation, reach out to the experts at AAA Foundation Service.
0% Financing for 18 Months